[Effects of different planting patterns on the apparent balance of soil nutrients and nitrogen production efficiency in paddy soil]. / ç¨»ç”°ä¸åŒç§æ¤æ¨¡å¼å¯¹åœŸå£¤å »åˆ†è¡¨è§‚å¹³è¡¡å’Œæ°®ç´ ç”Ÿäº§æ•ˆçŽ‡çš„å½±å“.

To investigate the effects of different planting patterns on soil nutrient contents, rice yield, nitrogen production efficiency, and apparent nutrient balance, a long-term field experiment was conducted in Changsha, Hunan, China. Four planting patterns were examined, including winter fallow-double cropping rice (CK), ryegrass-double cropping rice (Ry-R-R), Chinese milk vetch-double cropping rice (Mv-R-R), rape-double cropping rice (Ra-R-R). Compared with CK, soil total nitrogen (N) and available N were significantly higher under Ry-R-R, Mv-R-R and Ra-R-R. However, soil available potassium (K) content in CK was significantly higher than that in the other treatments. In addition, the N partial factor productivity in the late rice cropping was significantly higher under Ry-R-R, Mv-R-R and Ra-R-R. The N accumulation in panicles, stems and leaves of late rice under Ry-R-R, Mv-R-R and Ra-R-R were significantly higher than that in CK. Furthermore, the rice yield in Ry-R-R and Mv-R-R were significantly higher in comparison to CK. A significant positive correlation between grain yield and soil N content was observed. Compared with CK, Ry-R-R and Mv-R-R significantly increased the surplus of soil N and phosphorus content, but Ry-R-R and Ra-R-R increased the surplus of K content. Overall, winter crop-double rice cropping system could improve soil nutrient contents and N production efficiency, alleviate K deficiency, which would be beneficial to soil nutrient balance of paddy soils. Given the high surplus of N in paddy soils, N fertilizers should be reduced.

[Effects of Long-term Fertilization Regimes on Microbial Biomass, Community Structure and Activity in a Paddy Soil].

Four paddy soils were collected in Ningxiang County, Hunan province. These used with different long-term fertilization regimes, including a control without fertilizer (CK), chemical fertilization with nitrogen, phosphate, and kalium (NPK), straw fertilization combined with NPK (ST), and manure fertilization combinedwith NPK (OM). Phospholipid fatty acid (PLFA) technology and MicrorespTM method were used to study the effect of long-term fertilization on soil microorganism abundance, community structure, and activity. Results showed that the abundance of bacteria, fungi, gram-negative (G-) bacteria, and gram-positive (G+) bacteria in the soil from the OM treatment was generally higher than for the other treatments; these levels were lower in the ST and NPK treatments and lowest in the CK treatment. The principal components analysis (PCA) of PLFA showed that the community structure of microorganisms in NPK, ST, and OM treatments was altered in comparison with that in CK, especially in the case of the ST and OM treatments. MicroRespTM results revealed that compared to the CK treatment (1.28 µg·h-1), soil microorganisms in the OM treatment had the highest average utilization rate of multiple carbon sources (1.81 µg·h-1), followed by ST (1.19 µg·h-1), CK (1.28 µg·h-1), and NPK (0.95 µg·h-1). Furthermore, different long-term fertilization regimes resulted in distinct carbon source preferences for the soil microorganisms and revealed a significant alteration in the microbial community. Conclusively, long-term fertilizer with straw or manure changes the microbial community and is a benefit for improving the biomass and activity of microorganism in rice paddy soils.

Evaluation of the effects of the water-soluble total flavonoids from Isodon lophanthoides var.gerardianus (Benth.) H. Hara on apoptosis in HepG2 cell: Investigation of the most relevant mechanisms.

ETHNOPHARMACOLOGICAL RELEVANCE: The water-soluble total flavonoids (WSTF) were extracted from Isodon lophanthoides var. gerardianus (Benth.) H. Hara, a common folk herbal medicine in China, which has been recorded by the "Chinese Pharmacopoeia" in 2015 and used for prevention and clinical treatment of common diseases of liver and gall for many years. OBJECTIVE OF THE STUDY: The aim of this study is to evaluate the effects of WSTF on apoptosis in HepG2 cell and investigate the relevant mechanisms underlying. MATERIALS AND METHODS: Cytotoxicity was evaluated in HepG2 cells (human hepatoma cell lines) using MTT assay. The influence of the WSTF on the intracellular reactive oxygen species (iROS) and the mitochondrial membrane potential were also determinated. We used flow cytometry analysis to detect the effects of WSTF on apoptosis, cell cycle. Then we applied RT-PCR for genetic expression of main effectors and western blot analysis for activation of main effectors involved in the potential apoptosis signaling pathways. RESULTS: WSTF inhibited cell growth in HepG2 cells. Moreover, WSTF stimulates to increase amount of iROS, mitochondrial membrane potential, and the apoptotic relevant factors (cytochrome c, caspase-3) in HepG2 cells. WSTF could significantly induce apoptosis through downregulating apoptosis-antagonizing protein (Bcl-2, Survivin, mcl-1) and upregulating apoptosis-promoting proteins (Bax) and cell cycle G0/G1 arrest in HepG2 cells. CONCLUSION: The results indicate that WSTF induces cell apoptosis through mitochondrial pathway in the HepG2 cells. Therefore, these studies suggest that WSTF could be used as a chemotherapeutic agent to treat hepatoma.

[Determination of six C-Glycoside flavones and antitumor activity of water-soluble total flavonoids from Isodon lophanthoides var. gerardianus].

This research established an HPLC method for determination of six C-Glycoside flavones of warer-soluble total flavonoids from Isodon lophanthoides var. gerardianus (Benth.) H. Hara, and studied the antitumor activity of the warer-soluble total flavonoids. The HPLC system consisted of Kromasil 100-5 C18 (4.6 mm x 250 mm, 5 microm) column and a solution system of methanol, acetonitrile and 0.5% formic acid gradient elution at a flow rate of 0. 8 mL x min(-1) and the wavelength of detector was at 334 nm. The column temperature was 25 degrees C. The antitumor activity of water-soluble flavonoids was assayed using HepG2 cell as the tested cell. The linear ranges of vicenin II, vicenin III, isoschaftoside, schaftoside, vitexin, 6, 8-di-C-a-L-arabinosylapigenin were 0.25-2.53, 0.12-1.20, 0.37-3.69, 0.16-1.63, 0.19-1.92, 0.14-1.42 microg, respectively. The average recoveries (n = 6) were 99.6% (RSD 0.87%), 100.2% (RSD 2.0%), 99.6% (RSD 1.8%), 97.9% (RSD 1.5%), 98.8% (RSD 1.2%), 98.6% (RSD 1.2%), respectively. After exposure in 24, 48, 72 h, the total flavonoids showed inhibitory effect on the proliferation of HepG2 cells with IC50 as the evaluation index, the IC50 values of 1.89, 1.71, 1.51 g x L(-1), respectively. The method is quick, simple and accurate with good re- producibility, and can be used for determination of vicenin II, vicenin III, isoschaftoside, schaftoside, vitexin, 6, 8-di-C-a-L-arabino- sylapigenin in the warer-soluble total flavonoids from L lophanthoides var. gerardianus. The warer-soluble total flavonoids from L lophanthoides have inhibitory effect on the proliferation of HepG2 cells.